Digital Subscriber Line (DSL) technology is a broadband access technology that enables fast data transmissions to and from customer's premises over traditional telephone copper wires. Widely used DSL technologies include Asymmetric Digital Subscriber Line (ADSL) and Very High Speed Digital Subscriber Line (VDSL) technologies. Typically, ADSL technology is used at frequencies up to about two megahertz (MHz) and line distances up to about 6000 meters. VDSL technology is used at frequencies up to about 30 MHz and line distances up to about 1,500 meters. ADSL has evolved into VDSL as fiber optic lines have been increasingly deployed from provider distribution sites closer to customer premises. Currently, advanced VDSL (VDSL2) can provide bidirectional communications at about 100 megabits per second (Mbit/s) data rate in each direction using about 30 MHz bandwidth. In recent years, the access range for DSL has become shorter as the fiber optic lines have extended deeper towards user locations. The reduction in copper loop lengths allows using substantially wider frequency bandwidth than 30 MHz and thus higher data rates for broadband communications over copper wires.